A customer of ours, complained that when setting the reset vectorback to 0, it trashed other data and hung their box. They noticedwhen only 4 bytes were set to 0 instead of 8, everything workedcorrectly.

I don't know where to find this in the spec to know if this iscorrect, but looking at historical info of the code, x86_64 usedto use 'int' here whereas i386 used to use 'long'. When they gotmerged it seemed like 'long' was used. So the change seems tomake sense from that point of view.